Craftsmen such as carpenters, contractors, engineers, and cabinet makers, for example, repeatedly make use of several basic tools in their jobs. Some of the most commonly used tools include scales, squares, levels, protractors, straight edges, plumbs, among others. There have been numerous attempts in the past to combine several of these commonly used tools into one for convenience. For example, U.S. Pat. No. 4,481,720, issued to Sury, discloses a combined level and protractor in which the level spirit vials can be recalibrated. A protractor arm pivots from a recess within the main body to a 90.degree. position. A stop structure including a thumb wheel and a lead screw shaft can be used to fix the angular position of the protractor arm. In another example, U.S. Pat. No. 101,773, issued to Sharp, discloses a tool having a main body with a spirit level therein and an arm pivotable from the main body for use as a bevel. Finally, Warnock, in U.S. Pat. No. 359,372, discloses a combination tool having a pair of straight edges with spirit levels connected at right angles to each other for use as both a level and a plumb indicator.
Despite this long recognized need, no such combination tool has proved acceptable in the construction setting. Accordingly, there remains a need for a device combining both a level and a square along with an apparatus for measuring slopes and for determining plumb lines.